Gaius seems to be a leader in a church that John knew well. Presumably Diotrephes was keeping people from experiencing the help and welcoming nature that John assumes a Christian should ‘expect’. The church should be an open place, a welcoming place for other believers and leaders. The dividing issue was Diotrephes’ personal spiritual problem, not Gospel truth. Perhaps he was fearful or controlling, worried that another preacher might ‘steal’ his people.
But that is surmising. The principle is clear in this short letter – the local church is to be a place of truth and openness, not sectarian or closed.
Remember 2 John and 3 John provide us with a wonderful balance. Both sides are important.
Pic: St. John the Evangelist at Patmos – Alonzo Cano (1645)